At the end of the winter season, we often send out questionnaires to customers asking for a critique of winter performance. When an unfavorable reply comes to the office, contractors will bend over backwards to ensure the customer concerns are addressed in a satisfactory manner. Why not do the same with your subs? Give them feedback after the season, in writing, of what has bothered you (or your customers) about their performance.
Maybe the sub’s reporting or invoicing wasn’t up to par. How will they know if no one tells them of the issue? A written evaluation is not at all out of line. YOU are the subs’ customer. You might want to act like it. Too many times you could get the distinct impression the contractor is afraid of the sub. You give them way too much credit. They need your money, just like you need your customer’s money.